在嵌套用户控件中绑定DependencyProperty [英] Binding DependencyProperty in nested user controls

问题描述

我遇到了这个问题:我已经制作了2个用户控件:NestedControl1和NestedControl2. NestedControl2包含NestedControl1，而NestedControl1仅包含TextBlock. 我已经将每个NestedControl * DataContext设置为Self，并为每个对象创建了一个依赖项属性. NestedControl1.MyText1和NestedControl2.MyText2. 然后，将NestedControl2.MyText1绑定到MyText2，并将TextBlock.Text绑定到MyText1.

I've this problem: I've made 2 user controls: NestedControl1 and NestedControl2. NestedControl2 contains NestedControl1, and NestedControl1 contains just a TextBlock. I've set each NestedControl* DataContext to Self, and created a dependency property for each one. NestedControl1.MyText1 and NestedControl2.MyText2. Then I've bound the NestedControl2.MyText1 to MyText2, and the TextBlock.Text to MyText1 .

如果我在窗口上使用NestedControl2并将MyText2设置为任何值，它将无法正常工作.但是，如果我直接在Window上使用NestedControl1，它确实可以工作.关键是我想使MyText2的值到达NestedControl1内部的TextBlock.Text属性.

If I use the NestedControl2 on a Window and set MyText2 to whatever, it does not work. However if I use directly the NestedControl1 on a Window, it does work. The point is that I would like to make the value of MyText2 arrive to the TextBlock.Text property inside of NestedControl1 .

代码如下.怎么了???任何的想法??预先感谢tou提供的答案

The code is the following.. What's wrong?? Any idea?? Thank tou in advance for the answers

NestedControl2代码:

NestedControl2 code:

public partial class NestedControl2 : UserControl
{
    public NestedControl2()
    {
        InitializeComponent();
    }

    public static readonly DependencyProperty MyText2Property = DependencyProperty.Register(
        "MyText2", typeof(string), typeof(NestedControl2), new PropertyMetadata(default(string)));

    public string MyText2
    {
        get { return (string)GetValue(MyText2Property); }
        set { SetValue(MyText2Property, value); }
    }
}

NestedControl2 xaml:

NestedControl2 xaml:

<UserControl x:Class="TestNestedPropertiesWpf.NestedControl2"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:testNestedPropertiesWpf="clr-namespace:TestNestedPropertiesWpf"
         mc:Ignorable="d" 
         d:DesignHeight="300" d:DesignWidth="300"
          DataContext="{Binding RelativeSource={RelativeSource Self}}"
         HorizontalAlignment="Stretch" VerticalAlignment="Stretch">
<Grid>
    <testNestedPropertiesWpf:NestedControl1 MyText1="{Binding MyText2}" />
</Grid>

NestedControl1代码:

NestedControl1 code:

public partial class NestedControl1 : UserControl
{
    public NestedControl1()
    {
        InitializeComponent();

    }


    public static readonly DependencyProperty MyText1Property = DependencyProperty.Register(
        "MyText1", typeof(string), typeof(NestedControl1), new PropertyMetadata(default(string)));

    public string MyText1
    {
        get { return (string)GetValue(MyText1Property); }
        set { SetValue(MyText1Property, value); }
    }
}

NestedControl1 xaml:

NestedControl1 xaml:

<UserControl x:Class="TestNestedPropertiesWpf.NestedControl1"
         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:testNestedPropertiesWpf="clr-namespace:TestNestedPropertiesWpf"
         mc:Ignorable="d" 
         d:DesignHeight="300" d:DesignWidth="300" DataContext="{Binding RelativeSource={RelativeSource Self}}">
<Grid>
    <TextBlock Text="{Binding MyText1}" 
               x:Name="textBlock" Foreground="Red" 
               Width="300" Height="100" Background="Black"></TextBlock>
</Grid>

最后，这是MainWindow.xaml:

And in the end, this is MainWindow.xaml:

<Window x:Class="TestNestedPropertiesWpf.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:testNestedPropertiesWpf="clr-namespace:TestNestedPropertiesWpf"
    Title="MainWindow" Height="350" Width="525"  DataContext="{Binding RelativeSource={RelativeSource Self}}">
<StackPanel>
    <testNestedPropertiesWpf:NestedControl1 MyText1="WORKING"/>
    <testNestedPropertiesWpf:NestedControl2 MyText2="NOT WORKING"/>
</StackPanel>

推荐答案

我找到了解决方案. NestedControl2拥有自己的DataContext，并且使用NestedControl1拥有自己的DataContext，因此这两个DataContext是不同的. 为了解决该问题，我修改了MyText1中声明的绑定，如下所示:

I found the solution. The NestedControl2 had DataContext to self, and used NestedControl1, wich had DataContext to self, so the two DataContext were different. To solve the problem I modified the binding declared in the MyText1 like this:

<testNestedPropertiesWpf:NestedControl1 MyText1="{Binding RelativeSource={RelativeSource AncestorType={x:Type testNestedPropertiesWpf:NestedControl2}}, Path=MyText2}" />

这篇关于在嵌套用户控件中绑定DependencyProperty的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！